Question

I have a task to create a new rule that must catch all email messages which will be send to domain with exception – this rule can not concerns existing users.

For example:

I have three users:

[e-mail]

[e-mail]

[e-mail]

When somebody will send any email message to [e-mail], [e-mail]… all emails send to this addresses will be redirected to [e-mail].

In brief – when somebody send email on address that not exist in this domain, this message will be send to address [e-mail]

Answer 1

You can do this with a Transport Rule if you have something like an All Users group that contains all your valid users/groups/etc in the domain. Essentially you will create a transport rule that says “Redirect messages to if the message is from except if “. You’ll also need to disable the Recipient filtering anti-spam rule.

Generally speaking, though, this is a bad idea. You’re creating a mailbox that is going to be absolutely flooded with spam, will take alot of disk space, and will need constant cleanup. Make sure the mailbox has a quota. If you get hit with a deluge of spam, you don’t want this mailbox to use up all the disk space on the server and terminate service for your end user community.